METALLICA bassist Robert Trujillo says that there has been no discussion about more "Big Four" concerts before SLAYER finally calls it quits.

The so-called "Big Four" of 1980s thrash metal — METALLICA , MEGADETH , SLAYER and ANTHRAX — played together for the first time in history on June 16, 2010 in front of 81,000 fans at the Sonisphere festival at Bemowo Airport in Warsaw, Poland and shared a bill again for six more shows as part of the Sonisphere series that same year. They reunited again for several dates in 2011, including the last "Big Four" concert, which was held on September 14, 2011 at Yankee Stadium in New York City. Since then, METALLICA , SLAYER and ANTHRAX have played a number of shows together, including the 2013 Soundwave festival in Australia. They also performed at the 2014 Heavy MTL festival in Montreal, Quebec, Canada.

During an interview with Australia's "The Music" podcast, Trujillo was asked if the "Big Four" concept finally came to an end because SLAYER is wrapping things up with its farewell tour.

"To be honest, I haven't heard any conversations about the 'Big Four,'" Robert responded (hear audio below). "We love SLAYER — I love SLAYER ; they're one of my favorite bands. And ANTHRAX is amazing. And that was great what we did a few years back. But I haven't heard any conversations about that. I mean, obviously, we're still in the middle of our tour. And I'm not sure what [the other bands] are doing. I know, yeah, SLAYER is definitely on their final tour. I'm not even sure SLAYER 's up for that or what."

He continued: "It's a weird question, because it hasn't been talked about or discussed, because everybody is kind of in the middle of their stuff right now. So I don't even know how to answer that. But I can say it was an incredible experience, and we all had a blast. And it was something that no one thought could really be done, and then it happened. And it was a beautiful thing. But, you know, I think at some point, everybody kind of moves on and they get wrapped up in their stuff, and that's kind of where everybody's at right now."

Last year, MEGADETH leader Dave Mustaine said that he would love play a "Big Four" show where all the bands "got treated fairly" instead of METALLICA performing a longer set and getting more stage space than the other groups on the bill. "It always kind of soured to me when you watch [ METALLICA guitarist] Kirk Hammett say on the DVD [ 'The Big Four: Live From Sofia, Bulgaria' ], when they're praying, and he says that 'we're the Big One,'" Mustaine told SiriusXM . "That just kind of shows you how the mentality was there — that it really wasn't the 'Big Four'; it was METALLICA and then the three of us."

Mustaine added: "I would love to see it done in a way where we all got treated fairly and we all played together, same amount of time, same kind of stage situation, but I don't think that's gonna happen. And it's cool, because SLAYER 's gonna down in history, and they don't need the 'Big Four' to make them any more legendary than they already are. Nor do I."

Hammett said in a 2017 interview that he believed that the "Big Four" idea would be revisited again. He explained: "I see those shows as kind of like a celebration — a real celebration of each other, and a real celebration of the music that we all make, and a real celebration of the audience embracing [what] we've done. And why not have more of that?"

Six years ago, SLAYER frontman Tom Araya said that the only thing that was standing in the way of further "Big Four" shows was "the politics of character in one particular band," with some fans speculating that he was talking about Mustaine and MEGADETH .

In his autobiography, "Mustaine: A Heavy Metal Memoir" , Mustaine addressed the issue of where his band fit in the "Big Four" order. According to The New York Times , he assured the reader that he was not offended by being put behind SLAYER . But he added an interior monologue: "O.K., we'll play ahead of you guys on this trip, and God willing we'll do it again sometime in the near future and we can flip things around."